Plunger for box-making machines



Dec. 8, 1931. F. M.JosLlN 1,835,401

PLUNGER FOR .BOX MAKING MACHINES l Filed Fei?. 14, 1930 l 2 Sheets-Sheet 1 Y a f nl i Dec. 8, 1931. F. M '.JgosLlNl 1,835,401

PLUNGER FOR BOX MAKING MACHINES Filed Feb. 14, 1950 2 Sheets-Sheet 2 Patented Dec. 8, 1931 UNITED STATES'l FRANK M. JOSLIN, OF AMSTERDAM, NEW YORK PLUNGEB. Fon BOX-MAKING `iuncniiivns Application nea February 14, 1930. seria No. 428,470.

This invention relates to box-making machines of the type shown in my prior Patent No. 1,356,771, October 20, 1920, and directed particularly to certain detailed improveg ments over the machine of my copending application Serial No. 354,353, filed April 11, 1929. y l y In machines of this type, the plunger'is made up of two relatively movable parts, one part having wings pivotally supported thereon and adapted to be swung so as to bend inl wardly the edge portions on two opposite sides of a box, the wings being caused to operato by tbe relative movement between the if; two parts of the plunger. It has been found that in some cases, particularly with or deep boxes, there is a tendency forv the sides of the box to buckle or move inwardly as the wings bend the'outer edge portions 2S Jthereof inwardly-1, *i i i vlt istherefore an object of this invention to provide in a box machine of this type means which will prevent this inward move- AmentV or buckling of the box while the'edges thereof are being bent inwardly.

A further object of the invention is to provide means of that character which are yieldably held in position to support the sidesV A still further'objectis to provide meansV of this character 1n which members are slidably mounted on the lowerk portion of the plunger and spring pressed into position to support the sides of the box while the edges thereof are being bent and which are positively moved inwardly as the upper portion of the plunger descends into the die.Y

The invention in one specific form is illustrated in the accompanying drawings forming a part hereof and in which:

Figure 1 is a vertical sectional view of a plunger and die, the plunger having the invention applied thereto and certain parts in this ligure being shown in vertical elevation;

Figure 2 isa partial sectional lview similar to Fig. 1, the parts being shown in a different position and certain parts beingomitted,

17 secured to the upper portion of the Figure 3 is a partial vertical sectional view showing the lower portions of the plunger and the cooperating die, the parts in this ligure being shown in still a `different position; i

y 5^ FigureV 4 1s a transverse sectional view on the line 4-4-of Fig. 1; f

Figure 5 isa transversesectional -view on the line 5--5 of Fig. 4; and

Figure G is La perspective view of certain details of the device. y

In the accompanying drawings the invention is shown as appliedto a plunger identicalwith that described andcla-imed in my said copending application Serial N o. 354,353; andV detailed: illustration and description ofthe plunger and the means for operating the same are thought unnecessary in Vthis application. `Briefly, the plunger comprises a bottomA art and a body part 11 which are movab e relative to each other. The body part ll'includes upwardly projecting portions12 and a central portion 13,. which latter is oonnectedby a dovet-ailed joint to a crosshead letwhich is vertically reciprocated by suitable mechanism asset forth in saidV prior application. The bottom part 10 of the plunger includes standards 16 which extend'upwardly through the body part 11. The two parts 10 and 11 of the plunger are movable relative to each other. Latches are provided Vfor yieldably locking the two parts" of the plunger together in two different positions; These latches'e'ach comprise a casing body 'part 11' and containing a spring pressed ball 18 adaptedto engageupper and lower recesses 19,- 19ain the standard 16.

As fully set forth in said prior application, with the twoportions of the plunger locked together in the position shown in Figure 1, the crosshead ismoved downwardly which causes'the bottom part`10 of the plunger to enter 'the die 2O and foldthe blank, indicated at B, into the position shown in FigurerQ. Downward motion of the bottom part 1() Yis then stopped but the body part 11 continues to move downwardly into the die, this relative movement being permitted by yielding of the A latch connection between the two parts of the plunger. When the body part 11 reaches the lower limit of its movement, the two parts and 11 of the die are again locked together so that as the crosshead 14 moves upwardly, both parts of the plunger are lifted from the die. As such upward movement takes place, a cross bar 21 on the part 10 of the plunger strikes a lever 22 which arrests further movement of the part 10 but the upward movement of part 11 continues until the parts are again in the position shown in Figure 1.

After the blank B is yforced into the die and into the position shown in Figure 2, the edge portions E thereof on two opposite sides ,5 are bent inwardly. This is accomplished by means of the wings 25 which are pivotally supported on the standards of the bottom part 10 of the plunger and which-are vcaused to swing inwardly as the body part 11 there- V of descends, as illustrated in Figure 3.

As the edges E of the box are thus bent inwardly, there is a tendency to also bend inwardly or distort the sides of the box below said edges E and if the sides of the box are thus bent inwardly or buckled to any consideri able extent, the descending body part 11 of the plunger will strike the same and instead of merely forcing the edges E downwardly to complete the inward folding thereof, the sides themselves will be crushed and broken and the box destroyed. This difficulty is obviated by means of the present improvement.

A cross bar 30 is rigidly secured between the standards 16 of the bottom part of the :plungerabove the lower end thereof. Slidably mounted on the bar 30 are two members 31 which are arranged to move in suitable guides 32 secured to the bar 30. Each of the members-31 has connected thereto one end ofa spring 33, the other end of these springs being anchored to the cross bar 30 or to one of the guides 32vthereon. The springs 33 exert a constant pressure on the slidable members 31 and normally hold the same projected out- 15 wardly. The outer ends of the slidable bars l31 will thus be normally held close to the sides of the die or in position to support the sides of the box and prevent buckling or inward movement thereof as the upper edges are bent inwardl by the wings 25.

the following manner.

^11 ofthe plunger -are two downwardly extending bars 36 and the lower ends of these bars are. so positioned that when the body part 11 of the plunger descends, the bars 36 will strike the inclined surfaces 35 on the vplates 34'with the result that one of these in one direction and the other will be moved in the other direction. This movement of the bars 31 serves to retract the same or draw the free ends thereof inwardly so that they will be out of the path of movement of the body part 11 of the plunger as it moves into the die.

It will thus be seen that the members 31 act to support or prevent inward movement or distortion of the sides of the box while the wings 25 operate to bend the upper edges thereof inwardly. The term support is employed in the appended claims to define the functions of the bars 31. At the same time, when the body part 11 of the plunger moves downwardly into the die to complete the inward bending and folding of the edges E, the members 31 are retracted out of the way. When the plunger is again lifted from the. die, and the parts assume the position shown in Figure 1, the members 31 are again projected outwardly by the springs 33 into position to act when the plunger again descends. The extent of the outward movement of the members 31 is limited by contact of each of the plates 341 with the adjacent guide 32. The bars do not move outwardly suiiiciently to contact with the sides of the die or even with the folded sides of the box but when projected they lie sulliciently close to the sides of the box to perform the function above noted.

Modification of 'the details of the apparatus within the scope of the appended claims may be made without departing from the spirit of the invention.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A machine for making boxes from blanks comprising, in combination, a die, a plunger for forcing a blank into the die to form the same into a box, said plunger comprising two parts movable relative to each other, means on one part of said plunger for bending inwardly the upper edges on opposite sides of a box while in the die, and means mounted on the other part of said plunger for supporting the sides of the box during said bending operation.

2. A machine for making boxes from blanks comprising, in combination, a die, a plunger for forcing a blank into the die to form a box, means on said plunger for bending inwardly the upper edge on one side of the box while in the die, a member mounted on said plunger and movable laterally thereof into position to support the sides of the box during said bending operation, and means for moving said member out of said position.

3. A machine for making boxes from blanks comprising, in combination, a die, a plunger for forcing blanks into the die to llf:

form a box, means for bending inwardly the upper edges on opposite sides of the box while in the die, two members carried by said plunger and movable laterally thereof in opposite directions into position to support the sides of the box during said bending operation, and means for moving said members inwardly toward the plunger after said bending operation.

4l. A machine for making boxes Vfrom blanks comprising, in combination, aY die, a plunger for forcing a blank into the die to form a box, means for bending inwardly the upper edges on opposite sides of the box while in the die, two members carried by the plunger and movable laterally thereof in opposite directions into position to support the sides of the box during said bending operation, yieldable means for normally holding said members in said position and means for moving said members inwardly toward the plunger after saidA bending operation takes place.

5. A machine for making boxes from blanks comprising, in combination, a die, a plunger for forcing a blank into the die to form a box, pivoted wings carried by said plunger and arranged to bend inwardly the upper edges of a box while in the die, laterally movable members carried by said plunger below said wings, yieldable means for normally holding said members projected outwardly from said plunger to support the sides of the box during such bending operation,

' means for moving said wings abo-ut their pivoted supports and means for retracting said members after said bending operation.

6. A machine for making boxes from blanks comprising, in combination, a die, a plunger for forcing a. blank into the die to form a box, means for bending inwardly a portion of the edge of the box whilein the die, means carried by said plunger and movable laterally thereof for internally supporting the blank during such bending operation and means for retracting said supporting means after such bending operation.

7. A machine for making boxes from blanks comprising, in combination, a die, a plunger for forcing a blank into the die to form a box, said plunger including a bottom part and a body part, means for first moving the bottom part and then the body part of the plunger into the die, devices carried by said bottom part of the plunger for bending inwardly the upper edges on twoY opposite sides of the box after the bottom part of the iluno'er enters the die and while the boxis in the die, movable members carried by said bottom part of the plunger for supporting the sides of the box during said vbending operation, and means on the body part of the` plunger for operating Vsaid bending devices .f and for retracting saidmembers when the lcilody part of the-plungeris moved toward the 1e. j 1

8. -A construction is specified in claim 7 in which yieldable means are provided for projecting said members into position to support the sides of the box during the bending operation. i

9. A construction as specified in claim 7 in which said members are provided with inclined surfaces and in which said body part` of the plunger is provided with projections adapted to contact with said inclined surfaces, to thereby vretract said members.

10. A machine for making boxes from blanks comprising, in combination, a die, a plunger having abottom part adaptedto force a blank into the die to form a box, means for firstpmoving said bottom part of the plunger into the die, bendingdevices pivotally supported on said bottom part of the die for bending inwardly theupper edges'onopposite sides of the box while in the die, two members movably supported on said bottom part of the die, a spring for projecting each of said members outwardly into position to support the sides ofthe box during said bending operation, said plunger also having a body part movableinto the die, and means carried by said bodypart for ,operating said bending devices and for retracting said members inwardly against the action of said springs.

ll. A plunger adapted to cooperate with the die of a box-forming machine to form a box froma blank, said plunger comprising a bottom part and a body part movable relative to each other, said bottom part having devices thereon for bending inwardly the outer edges on two'v opposite sides of a box while the same is in the die and also having members movably mounted thereon for supporting the sides of the box during such bending operation, and means for operating said bending devices and retract-ing said j members when said body part of the plunger is moved relative to the bottom part.

12. A plunger adapted to cooperate with the die of a box-forming machine to form a box from a blank, said plunger comprising a bottom part and a body part movable relative to each other, said bottom part having devices pivotally mounted thereon for bending inwardly the outer edges on two opposite sides of a box while the same is in the die and also having members movably mounted thereon for supporting the sides of the box during said bending operation, springs for normally holding said members projected outwardly from said bottom part ofthe plunger, and means for operating said bending devices and retracting said members when said body part of the plunger is moved. relative to the bottom part.

` 13. A plunger for box-forming machines having ldevices pivotally mounted thereon for bending inwardly the edge portions on two opposite sides of a box, and also having members movably mountedthereon for Supporting the sides of the box during such bending operation, and means for yieldably holding said members in position to support the sides of a box.

14. A plunger for box-forming machines having device-s pivotally mounted thereon for bending inwardly the edge portions on two opposite sides of a box and also having two members movably mounted thereon for supporting the sides of the box during such bending operation, said members being arranged below said bending devices and springs for normally holding said members in position to support the sides of a box.

l5. A plunger for box-forming machines, said plunger comprising two parts movable relative to each other, means carried by one of said parts for folding inwardly thefedge of a box blank and other means for supporting said blank during the folding operation and means carried by the other part for controlling the operation of said folding and supporting means.

16. A plunger for box-forming machines, Said plunger comprising two parts movable toward and from each other, folding devices pivotally supported on one of said parts and `supporting devices slidably mounted on said last named part and means carried `by the other part for operating said folding devices and retracting said supporting devices when the two parts of the die move toward each 35. Y

other.

In testimony whereof I hereunto aflix my signature.

FRANK M. JOSLIN. 

